﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net.Sockets;
using System.Threading;
using System.Net;

namespace BL
{
    public class StateObject
    {
        // Client  socket.
        public Socket workSocket = null;
        // Size of receive buffer.
        public const int BufferSize = 1024;
        // Receive buffer.
        public byte[] buffer = new byte[BufferSize];
        // Received data string.
        public StringBuilder sb = new StringBuilder();       
    }
    
    
    
    public class Server
    {
        // Thread signal.
        private ManualResetEvent allDone;
        private volatile bool live;
        private int port;


        /// <summary>
        /// Constructor that initializes server and sets port.
        /// </summary>
        /// <param name="port">Server port</param>
        public Server(int port)
        {
            this.port = port;
            this.live = true;
            this.allDone = new ManualResetEvent(false);
        }


        public void StartListening()
        {
            // Establish the local endpoint for the socket.
            // The DNS name of the computer
            IPHostEntry ipHostInfo = Dns.GetHostEntry(Dns.GetHostName());
                
            //Dns.Resolve(Dns.GetHostName());
            IPAddress ipAddress = ipHostInfo.AddressList[1];
            
            IPEndPoint localEndPoint = new IPEndPoint(ipAddress, port);

            // Create a TCP/IP socket.
            Socket listener = new Socket(AddressFamily.InterNetwork,
                SocketType.Stream, ProtocolType.Tcp);

            // Bind the socket to the local endpoint and listen for incoming connections.
            try
            {
                listener.Bind(localEndPoint);
                listener.Listen(100);
                
                while (live)
                {
                    // Set the event to nonsignaled state.
                    allDone.Reset();

                    // Start an asynchronous socket to listen for connections.
                    Console.WriteLine(DateTime.Now.ToLongTimeString() + ": Waiting for a connection...");

                    listener.BeginAccept(
                        new AsyncCallback(AcceptCallback),
                        listener);

                    // Wait until a connection is made before continuing.
                    allDone.WaitOne();
                }

            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }

        }

        public void AcceptCallback(IAsyncResult ar)
        {
            // Signal the main thread to continue.
            allDone.Set();

            // Get the socket that handles the client request.
            Socket listener = (Socket)ar.AsyncState;
            Socket handler = listener.EndAccept(ar);

            // Create the state object.
            StateObject state = new StateObject();
            state.workSocket = handler;


            Send(handler, "penis penis penis");
            //TODO: REMOVE
            //handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
                //new AsyncCallback(ReadCallback), state);

            //handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
            //    new AsyncCallback(ReadCallbackTest), state);
        }

        public void ReadCallback(IAsyncResult ar)
        {
            String content = String.Empty;

            // Retrieve the state object and the handler socket
            // from the asynchronous state object.
            StateObject state = (StateObject)ar.AsyncState;
            Socket handler = state.workSocket;

            // Read data from the client socket. 
            int bytesRead = handler.EndReceive(ar);




            if (bytesRead > 0)
            {

                byte[] hej = state.buffer;
                byte[] decrypted = EncryptionProvider.Decrypt(hej, "password");
                string AppendedMessages = Compress.Deccompress(decrypted);
                
                string[] messageStrings = AppendedMessages.Split('*');

                foreach (string message in messageStrings) 
                {

                    MessageHandling.HandleIncommingMessage(message);
                }

                // Check for end-of-file tag. If it is not there, read 
                // more data.
                //content = message;
                if (content.IndexOf("<EOF>") > -1)
                {
                    // All the data has been read from the 
                    // client. Display it on the console.
                    Console.WriteLine("Read {0} bytes from socket. \n Data : {1}",
                        content.Length, content);
                    // Echo the data back to the client.
                    //Send(handler, content);
                }
                else
                {
                    // Not all data received. Get more.
                    handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
                    new AsyncCallback(ReadCallback), state);
                }
            }
        }

        public void ReadCallbackTest(IAsyncResult ar)
        {

        }

        private void Send(Socket handler, String data)
        {
            // Convert the string data to byte data using ASCII encoding.
            byte[] byteData = Encoding.ASCII.GetBytes(data);

            // Begin sending the data to the remote device.
            handler.BeginSend(byteData, 0, byteData.Length, 0,
                new AsyncCallback(SendCallback), handler);
        }

        private void SendCallback(IAsyncResult ar)
        {
            try
            {
                // Retrieve the socket from the state object.
                Socket handler = (Socket)ar.AsyncState;

                // Complete sending the data to the remote device.
                int bytesSent = handler.EndSend(ar);
                Console.WriteLine("Sent {0} bytes to client.", bytesSent);

                handler.Shutdown(SocketShutdown.Both);
                handler.Close();

            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
        }

        public void StopListening() 
        { 
            live = false; 
            allDone.Set(); 
        }

    }
}
